On most construction projects, risk is carefully allocated on paper long before work begins. Contracts define responsibilities, insurance policies are agreed, and method statements are approved. Yet beneath the ground surface, uncertainty often remains.
The question that repeatedly emerges is simple but critical: who owns the underground risk? Is it the client, the designer, the contractor, or the utility provider?
In reality, the answer is often blurred, and that lack of clarity can lead to delays, unexpected costs, and strained relationships across the project team.
This is where Ground Penetrating Radar (GPR) surveys play a vital role. By providing reliable subsurface data early, GPR helps reduce ambiguity, clarify responsibilities, and shift risk from assumption to evidence.
Despite advances in digital design, underground conditions are still one of the least certain elements of a construction project. Historic records may be incomplete, utility drawings may be inaccurate, and previous site uses may be poorly documented. On brownfield or urban sites, services are frequently layered, redundant, or diverted without proper records.
When projects rely on assumptions rather than verified data, risk is often pushed down the supply chain. Contractors may be expected to price unknown conditions, designers may work with incomplete information, and clients may assume that risk is covered somewhere in the contract.
This is particularly problematic under modern procurement routes, where collaboration and early contractor involvement are encouraged, but risk transfer is still heavily scrutinised. Without objective subsurface information, disputes over who should have known what and when are almost inevitable.
Underground risk is not just a technical concern; it is a commercial one. Unexpected services or obstructions can lead to programme delays, redesign costs, compensation events, and claims. In some cases, they can trigger health and safety incidents or service strikes that carry regulatory consequences and reputational damage.
Contractors may include risk premiums, while clients may challenge variations that arise from conditions they believed were already accounted for. The absence of reliable data makes it difficult for any party to demonstrate whether an issue was foreseeable or genuinely unforeseen.
GPR surveys help change this dynamic by replacing uncertainty with evidence. When subsurface conditions are investigated and documented early, risk can be allocated more fairly and transparently.
Ground Penetrating Radar uses high-frequency radar waves to detect changes in material beneath the surface, identifying utilities, voids, foundations, ducts, and other buried features. When carried out by experienced surveyors, GPR provides a clear, mapped picture of what lies below, allowing teams to make informed decisions before excavation begins.
This information becomes particularly valuable during early project stages. Designers can adapt layouts to avoid clashes, contractors can plan safe excavation methods, and clients can understand the true constraints of their site. Most importantly, everyone is working from the same verified dataset.
By introducing GPR early, underground risk becomes visible and measurable rather than hypothetical. This allows responsibilities to be defined based on known conditions, rather than assumptions that later unravel.
One of the most overlooked benefits of GPR is its role in supporting fair and reasonable risk allocation. When subsurface surveys are completed before contracts are finalised, they help inform scopes of work, employer’s requirements, and risk registers.
For developers and clients, this means fewer surprises and a stronger position when setting project budgets and programmes. For designers, it provides confidence that their proposals are grounded in reality, reducing the likelihood of late-stage changes. For contractors, it limits exposure to unknown conditions that are difficult to price or manage safely.
Clear subsurface data also strengthens collaboration. When all parties have access to the same information, discussions shift from blame to solutions.
Many construction disputes originate from differing interpretations of site conditions. Claims often hinge on whether a buried feature was reasonably foreseeable or whether sufficient investigations were undertaken. GPR surveys provide a defensible record of what was known at a given point in time.
This documentation is invaluable if questions arise later. In dispute resolution scenarios, objective survey data often carries significant weight, reducing the likelihood of prolonged claims or litigation.
In practical terms, investing in GPR early can save far more than it costs by avoiding disputes, programme overruns, and damaged working relationships.
UK construction continues to move towards greater accountability, transparency, and risk management. Initiatives around building safety, asset information, and digital records all reinforce the need for accurate data throughout a project lifecycle.
GPR surveys align directly with these expectations. They support safer excavation practices, help protect existing services, and contribute to a clearer understanding of site constraints. For duty holders, this proactive approach demonstrates a commitment to managing foreseeable risks rather than reacting to incidents after they occur.
As projects become more complex and sites more constrained, the expectation that underground risks are properly investigated will only increase. Which is why a GPR survey is needed on your site today!
If you want clarity on what lies beneath your site and confidence in how underground risk is managed, Intersect Surveys can help!
Our experienced team delivers high-quality GPR surveys that provide accurate, easy-to-interpret data to support early decision-making, safer construction, and fair risk allocation.
Whether you are at feasibility stage, developing designs, or preparing for construction, we work with you to ensure subsurface conditions are understood before they become a problem.
To discuss your project or arrange a GPR survey, contact Intersect Surveys today via our website or speak directly with our team. The sooner you understand the ground beneath your project, the stronger your position will be above it.